JP2003156650A - Optical fiber array and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical fiber array which has excellent adhesiveness between a groove for storing an optical fiber and an adhesive, which does not cause peeling between the surface of the groove and the adhesive and the displacement of the optical fiber, and accurately transmits an optical signal. SOLUTION: In the optical fiber array, a plurality of grooves are formed on part of the upper surface of a substrate, and an optical fiber is stored in the groove through the adhesive. A coupling agent layer is formed at least on the surface of the groove.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an optical fiber array.

[0002]

2. Description of the Related Art In recent years, attention has been focused on optical fibers mainly in the communication field. Particularly in the IT (information technology) field, communication technology using optical fibers is required to maintain a high-speed Internet network. Optical fiber has the features of low loss, high bandwidth, small diameter / light weight, no induction, resource saving, etc. In the communication system using the optical fiber having this feature, the communication using the conventional metallic cable is used. Compared with the system, the number of repeaters can be greatly reduced, construction and maintenance are facilitated, and the communication system can be made economical and highly reliable.

Further, in the optical fiber, not only the light of one wavelength but also the light of many different wavelengths can be simultaneously multiplexed and transmitted by one optical fiber, so that it has a large capacity for various purposes. This has a great advantage that a transmission line can be realized and a video service can be supported.

In optical communication using an optical fiber, an optical fiber ribbon in which a plurality of optical fibers are arranged in parallel and a coating resin layer is formed around the optical fibers is used. Then, this optical fiber ribbon is used for a light receiving element, a light emitting element, various terminal devices (personal computer, mobile, game, etc.)
In order to connect with the optical fiber ribbon, the coating resin layer at the end of the optical fiber ribbon is usually removed to expose the ends of the plurality of optical fibers, and the exposed optical fibers are mounted in the groove of the substrate having the V groove. There is used an optical fiber array in which a plurality of optical fibers are arranged at a predetermined interval by being placed and fixed.

Therefore, conventionally, as an optical fiber array, for example, an optical fiber in which the optical fibers are housed in alignment with each of a plurality of V grooves formed in a substrate and the optical fibers are fixed via an adhesive agent is used. It is disclosed.

[0006]

In such an optical fiber array, when the optical fiber array is connected to an optical element or when an external force is applied to the optical fiber array,
Positional deviation of the optical fiber may occur, resulting in defective connection between the optical fiber array and the optical element such as the light receiving element or the light emitting element. Further, when reliability evaluation such as a heat cycle test is performed using such an optical fiber array, peeling may occur between the substrate surface (groove surface) and the adhesive. It is considered that such positional displacement of the optical fiber and peeling of the adhesive occur due to insufficient affinity (adhesion) between the substrate surface (groove surface) and the adhesive.

That is, when manufacturing an optical fiber array, usually, after a substrate having a groove formed in a part of its upper surface is manufactured, the optical fiber is housed in this groove, and thereafter, uncured from the end face of the substrate. The optical fiber is fixed in the groove by pouring the adhesive of No. 1 and then curing the uncured adhesive, but depending on the surface condition of the groove, when the uncured adhesive is poured, the uncured adhesive is not cured. In some cases, the adhesive was not evenly poured, and there was a portion where the adhesive was not filled, or bubbles were generated in the filled adhesive. This was considered to be one of the causes of the positional deviation of the optical fiber and the peeling of the adhesive.

[0008]

Therefore, the present inventors have
As a result of diligent studies on the means for solving the above-mentioned various problems, it was found that the adhesion between the surface of the groove of the substrate and the adhesive should be improved. The inventors have found that it is sufficient to form a coupling agent layer, and completed the optical fiber array of the present invention and the manufacturing method thereof.

That is, the optical fiber array of the present invention is
An optical fiber array in which a plurality of grooves are formed in a part of the upper surface of a substrate, and an optical fiber is housed in the groove via an adhesive, and a coupling agent layer is formed on at least the surface of the groove. It is characterized by being

In the optical fiber array of the present invention, it is desirable that a coupling agent layer is formed on the upper surface of the substrate including the surface of the groove and / or on the surface of the optical fiber.

Further, in the optical fiber array of the present invention, it is desirable that a lid is formed on the substrate, and in this case, the upper surface of the substrate including the surface of the groove and the lid of the substrate are opposed to each other. It is desirable that a coupling agent layer be formed on the surface and on at least one of the surfaces of the optical fiber.

In the optical fiber array of the present invention, the coupling agent layer is preferably formed by using epoxysilane and / or imidosilane.

The method for manufacturing an optical fiber array of the present invention is characterized by including at least the following steps (A) to (D). (A) A groove forming step of forming a plurality of grooves on a part of the upper surface of the substrate, (B) a coupling agent layer forming step of forming a coupling agent layer on at least the surface of the groove, and (C) an optical fiber in the groove. Optical fiber storing step for storing
(D) An adhesive filling step of filling an uncured adhesive into the optical fiber non-enclosed portion of the groove.

In the method for manufacturing an optical fiber array of the present invention, it is desirable that at least the surface of the groove is subjected to plasma treatment and / or oxidation treatment before the step (B).

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the optical fiber array of the present invention will be described. The optical fiber array of the present invention, a plurality of grooves are formed in a part of the upper surface of the substrate, in the groove, an optical fiber array containing an optical fiber via an adhesive, at least on the surface of the groove, It is characterized in that a coupling agent layer is formed.

In the optical fiber array of the present invention, the coupling agent layer is formed on at least the surface of the groove formed on the substrate, and the surface of the groove having the coupling agent layer is formed with the adhesive. Since the optical fiber array is excellent in adhesion, peeling does not occur between the surface of the groove and the adhesive and the positional deviation of the optical fiber does not occur, and the optical fiber array is The optical signal can be transmitted to. In addition, when a coupling agent layer is formed on the surface of the groove, when the uncured adhesive is poured from the end surface of the groove during manufacturing, the uncured adhesive will not separate the groove and the optical fiber. Since it will be evenly poured into the gap, voids will not occur in the adhesive after the curing treatment.

The optical fiber array of the present invention will be described below with reference to the drawings. FIG. 1A is a partial perspective view schematically showing an example of the optical fiber array of the present invention, and FIG. 1B is a sectional view taken along line AA of FIG.

As shown in FIG. 1, the optical fiber array 10
0, a coupling agent layer (not shown) is formed in a plurality of V grooves 157 formed in parallel on the substrate 151, and the optical fiber 115 attaches the adhesive 159 to each of the V grooves 157. It is stored through. Also, the substrate 15
In addition to the groove 157, a coating resin layer holding portion 158 for holding the optical fiber together with the surrounding coating resin layer 114 is formed on the upper surface of the first surface. The upper surface of the coating resin layer holding portion 158 is lower than the groove forming surface in which the groove 157 is formed. Further, an adhesive layer 159 ′ is formed around the coating resin layer 114 placed on the coating resin layer holding portion 158. The coating resin layer holding portion 158 may be formed as needed, and only the V groove may be formed on the substrate. Also, in the figure, 11
Reference numeral 0 is an optical fiber ribbon, 111 is a core, and 112 is a clad.

When forming the coating resin layer holding portion together with the groove on the upper surface of the substrate, the boundary between the groove forming surface and the coating resin layer holding portion may be a vertical wall surface. It is desirable that the wall surface has an inclination so that it goes down toward the coating resin layer holding portion as shown. This is because when the optical fiber is stored, the load applied to the optical fiber can be reduced. In the present specification, the wall surface of the boundary between the groove forming surface and the coating resin layer holding portion is also included in the coating resin layer holding portion. Further, in the optical fiber array in which the boundary between the groove forming surface and the coating resin layer holding portion is a wall surface having an inclination, the exposed optical fiber is fixed in the groove, and the exposed optical fiber is fixed in the coating resin layer holding portion. The fiber and the coating resin layer are fixed.

Further, instead of the covering resin layer holding portion, a recess may be formed on the substrate, which can accommodate the optical fiber together with the surrounding covering resin layer. The shape of the concave portion here may be, for example, the same as the upper surface of the substrate at the lateral outer edge of the coating resin layer holding portion shown in FIG.
Alternatively, a shape having a wall surface lower than this may be used.

FIG. 2 (a) is a partial perspective view schematically showing an example of the optical fiber array of the present invention in which a lid is formed, and FIG. 2 (b) shows only the lid attached to the optical fiber array. It is a perspective view shown, (c) is a sectional view on the AA line of (a). As shown in FIG. 2, the optical fiber array 102 of the present invention is a substrate 1 that houses an optical fiber ribbon 110.
A lid 160 may be formed on the cover 51, and the lid 160 may be a recess for accommodating a part of the optical fiber 115 (a part of the optical fiber that has not been housed in the groove 157). 161 is formed. In addition, the recess 16
An adhesive 159 is also filled in the gap between the optical fiber 1 and the optical fiber. Further, the outer edge portion of the substrate 151 and the outer edge portion of the lid 160 are in close contact with each other via an adhesive (not shown). The optical fiber array 102 shown in FIG.
Although it is different from the optical fiber array 100 shown in FIG. 1 in that 0 is formed, other configurations are substantially the same as the optical fiber array 100.

In the optical fiber array of the present invention, when the lid is attached on the substrate, the shape of the lid is
For example, it may have a flat plate-like body or a shape in which a groove for separately accommodating an optical fiber is formed on the surface facing the substrate, but a part of the optical fiber as shown in FIG. It is desirable to have a shape in which a concave portion for accommodating is collectively formed. The recess for accommodating all the optical fibers is
It is easy to form, and since there is a gap between the optical fibers housed in the recesses, the relative positional deviation of the optical fibers is unlikely to occur, and furthermore, an adhesive is used in the gap. This is because it is easy to fill the like.

In the case where the lid is provided with a recess for accommodating the optical fibers all together, the shape of the recess is formed by combining only planes intersecting at right angles, or by a curved surface. A shape, a shape combining a flat surface and a curved surface, and the like can be given. The depth of the recess is
It is desirable that the height is the same as the height of the portion of the optical fiber which is not accommodated in the groove. Further, the lid portion may have a cross-sectional shape in a direction perpendicular to the axis of the optical fiber such that both lateral lower portions of the rectangle are cut off. Examples of the formed shape include a triangle, a quadrangle, a polygon, and a shape surrounded by two straight lines orthogonal to an arc (elliptic arc).

The lid may have a shape that covers the entire surface of the substrate (a shape that integrally covers each of the grooved region and the coating resin layer holding portion). Further, a lid having a shape that covers the region where the groove of the substrate is formed may be separately attached to the substrate, and a lid that has a shape covering the coating resin layer holding portion may be separately attached. Further, in this case, a gap may or may not be formed between the lid portion having a shape that covers the region where the groove is formed and the lid portion that has a shape that covers the coating resin layer holding portion. .

The optical fiber array 1 shown in FIGS.
In Nos. 00 and 102, four optical fibers are accommodated, but the number of optical fibers accommodated in the groove of the optical fiber array of the present invention is not limited to four, and three optical fibers are accommodated.
The number may be less than or equal to 5 or may be greater than or equal to 5.

In such an optical fiber array, a coupling agent layer is formed on the surface of the groove 157. In the optical fiber array of the present invention, since the coupling agent layer is formed at least on the surface of the groove formed on the substrate, the adhesiveness between the surface of the groove and the adhesive is excellent, and between the groove and the adhesive. Peeling does not occur, and the positional deviation of the optical fiber does not occur due to this peeling.

The coupling agent layer can be formed by using, for example, a silane-based, titanium-based, organic phosphoric acid-based, silyl peroxide-based coupling agent or the like.

Examples of the silane coupling agent include imidosilane, epoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane and γ-. Aminopropyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxysilane, phenyltriethoxysilane,
Trifluoropropylmethidimethoxysilane and the like can be mentioned. Further, trimethylsilyl isocyanate, dimethylsilyl diisocyanate, vinylsilyl triisocyanate, phenylsilyl triisocyanate and the like can also be used.

Further, as the titanium-based coupling agent,
For example, isopropyl triisostearoyl titanate, isopropyl tridecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis ( Di-tridecyl)
Examples thereof include phosphite titanate, bis-dioctyl pyrophosphate) oxyacetate titanate, and tris (dioctyl pyrophosphate) ethylene titanate.

The coupling agent layer may be formed on at least the surface of the groove, but is preferably formed on the upper surface of the substrate including the surface of the groove. In particular, when the lid is formed on the substrate, it is desirable that the coupling agent layer is formed on at least a portion of the upper surface of the substrate facing the lid. This is because when the lid is formed, the lid is usually attached to the substrate via an adhesive, and in this case, the adhesive also comes into contact with the groove-unformed portion on the upper surface of the substrate. The coupling agent layer may be formed on the entire top surface of the substrate. This is because the formation is easy.

The method for forming the coupling agent layer is not particularly limited and may be appropriately selected depending on the type of coupling agent. The method of forming the coupling agent layer will be described in detail when the method of manufacturing the optical fiber array of the present invention is described.

Further, an oxide film may be formed on the surface of the groove at least before forming the coupling agent layer on the surface of the groove. By forming an oxide film on the surface of the groove in advance, the surface of the groove can be made substantially uniform, and the coupling agent layer formed thereon can also be made substantially uniform. Therefore, when the optical fiber is housed in the groove and the uncured adhesive is filled between the groove (coupling agent layer) and the optical fiber, the uncured adhesive can be filled in a uniform state. Adhesion with the groove (coupling agent layer) can be achieved without forming an unfilled part between the groove and the optical fiber and without generating voids in the adhesive after the curing process. This is because the adhesiveness with the agent can be improved.

As a method of forming an oxide film on the surface of the groove, for example, an oxidization treatment using a mixed solution of sulfuric acid and hydrogen peroxide, an oxidization treatment using a fuming nitric acid solution, an oxidization treatment for heating a substrate, etc. Is mentioned. The detailed contents of each of these oxidation treatments will be described in the method for manufacturing an optical fiber array of the present invention described later.

Here, an oxide film is formed on the surface of the groove,
When the substrate is made of silicon, the degree of oxidation of the oxide film is
The lower limit is preferably 0.1 nm and more preferably 10 nm. The upper limit of the degree of oxidation is preferably 1000 nm, more preferably 300 nm, and particularly preferably 100 nm. When the degree of oxidation is in this range, the oxide film formed on the surface of the groove can be made almost surely uniform, so that the coupling agent layer formed on it can also be made almost surely uniform. Because you can do it.

In the present specification, the above-mentioned degree of oxidation means ESCA (Electron Spectroscopy For Chemical An
alysis). In the ESCA, the substrate is irradiated with monochromatic soft X-rays in vacuum, and the energy of the emitted electrons is spectroscopically analyzed to evaluate the constituent elements and the oxidation state of the surface.

Further, the portion of the surface of the substrate where the coupling agent layer is formed may be previously subjected to plasma treatment. By subjecting the portion of the surface of the substrate on which the coupling agent layer is formed to a plasma treatment in advance, the surface condition of the substrate is made uniform and foreign substances can be removed and formed on it. The coupling agent layer can be made substantially uniform. Therefore, when the optical fiber is housed in the groove and the uncured adhesive is filled between the groove (coupling agent layer) and the optical fiber, the uncured adhesive can be filled in a uniform state. The groove (coupling agent layer) and the adhesive can be formed without causing a portion not filled with the uncured adhesive between the groove and the optical fiber or generating a void in the cured adhesive. This is because the adhesion with can be improved.

Examples of the plasma treatment include a method using at least one selected from oxygen, nitrogen, carbon dioxide, argon, carbon tetrachloride, carbon tetrafluoride and the like. The specific processing conditions and the like of the plasma processing will be described in detail when the method for manufacturing an optical fiber array of the present invention is described.

Further, the portion of the substrate where the coupling agent layer is formed may be previously subjected to pretreatment such as cleaning treatment and acid treatment. By performing such pretreatment, the surface state of the substrate becomes uniform, and the state suitable for forming the coupling agent layer is obtained. The pretreatments such as cleaning treatment and acid treatment will be described in detail when explaining the method for producing an optical fiber array of the present invention.

Even if the above-mentioned oxide film is formed on the surface of the substrate where the coupling agent layer is to be formed, the above-mentioned plasma treatment, cleaning treatment, acid treatment and the like pretreatment is performed. Good. This is because the surface condition of the oxide film becomes more uniform and the surface condition of the coupling agent layer formed thereon also becomes more uniform.

The material of the substrate in which the groove is formed is, for example, silicon, silicon carbide, alumina, aluminum nitride, mullite, ceramic, gallium arsenide,
Inorganic materials such as zirconia, quartz, glass; metal materials such as copper, iron, nickel; thermosetting resins, thermoplastic resins, photosensitive resins, organic materials such as composites thereof, and glass fibers for these organic materials And the like impregnated with the reinforcing material. Among these, expansion and contraction (deformation) due to heat and humidity
Silicon is desirable because it has a small amount and has excellent mechanical strength. In the case of a substrate made of silicon, deformation and waviness of the optical fiber are unlikely to occur when the optical fiber is housed, and inconvenience is unlikely to occur when an optical signal is transmitted through the optical fiber.

Further, when the lid is formed on the substrate of the optical fiber array of the present invention, it is desirable that the coupling agent layer is also formed on the surface of the lid facing the substrate. The lid is usually attached to the substrate via an adhesive, and by forming a coupling agent layer on the surface of the lid facing the substrate, the adhesion between the lid and the adhesive is improved. Because it improves. Therefore, the coupling agent layer may be formed only on the portion of the surface of the lid portion that comes into contact with the adhesive. In addition, when a lid part having a shape covering the grooved region of the substrate and a lid part having a shape covering the coating resin layer holding part are separately attached, a lid part having a shape covering the coating resin layer holding part is attached. It is desirable that the coupling agent layer is also formed on the surface facing the substrate. The coupling agent layer formed on the surface of the lid portion facing the substrate can be formed by, for example, the same method as the method of forming the coupling agent layer on the surface of the groove.

Examples of the material of the lid include the same materials as those of the substrate. The material of the lid and the material of the substrate may be the same,
It may be different.

The material of the lid is preferably glass or quartz, and particularly preferably heat-resistant glass having a softening point of 500 ° C. or higher. When a lid made of glass or quartz is used, a cured product of an ultraviolet curable resin composition may be used as an adhesive for fixing the optical fiber in the groove or an adhesive filling between the lid and the substrate. it can. This is because the lid made of these materials transmits ultraviolet rays. When using a lid made of a material that does not transmit light such as ultraviolet rays, a resin composition containing at least a thermosetting resin is used as an adhesive or the like for fixing the optical fiber in the groove.

The optical fiber array 1 shown in FIGS.
In Nos. 00 and 102, the optical fiber ribbon 110 in which the optical fiber is exposed by removing the coating resin layer at one end is stored in the substrate 151 in which the plurality of V grooves 157 are formed. The optical fiber ribbon is not particularly limited, and a conventionally known one can be used. For example, the primary coating resin layer 113 is provided around the optical fiber 115 including the core 111 and the clad 112 as shown in FIG.
It is possible to use the optical fiber ribbon 110 in which the optical fibers 115 coated with the primary coating resin layer 113 are arranged in parallel and are collectively coated with the secondary coating resin layer 114.

Optical fiber 1 constituting an optical fiber ribbon
As 15, there are, for example, a silica-based optical fiber whose main component is silica glass (SiO ₂ ), a multi-component optical fiber whose main component is soda lime, glass, borosilicate glass, and a plastic such as silicone resin or acrylic resin. Examples include plastic optical fibers containing as a main component. Of these, quartz optical fiber is desirable. By forming a roughened surface on the surface, the adhesiveness with the adhesive is particularly improved, which is suitable for the optical fiber array of the present invention.

The primary coating resin layer 113 plays a role as a protective layer for preventing the optical fiber from being damaged. The material is not particularly limited,
For example, a thermosetting resin such as an epoxy resin, a silicone resin, a urethane resin, a phenol resin, a polyimide resin, a polyolefin resin, or a fluororesin, or methacrylic acid or acrylic acid is used, and the thermosetting group of the thermosetting resin described above is used. Examples thereof include (meth) acrylated photosensitive resins. The number of the primary coating resin layers is not limited to one and may be two or more.

The secondary coating resin layer 114 plays a role of protecting the optical fiber formed around the primary coating resin layer and maintaining the shape of the optical fiber ribbon in which the optical fibers are arranged in parallel. There is. The material is not particularly limited, and examples thereof include the same thermosetting resin and photosensitive resin as the material of the primary coating resin layer. The number of the secondary coating resin layers is not limited to one, and
It may be more than one layer.

In the optical fiber arrays 100 and 102, it is desirable that the coating resin layer is removed and a roughened surface (not shown) is formed on the surface of the optical fiber housed in the V groove 157. . This is because the adhesion between the optical fiber and the adhesive is improved. The average roughness Ra of the roughened surface preferably has a lower limit of 1 nm and an upper limit of 100 nm. Average roughness Ra
However, if it is less than 1 nm, the adhesiveness between the optical fiber and the adhesive is hardly improved. On the other hand, if the average roughness Ra exceeds 100 nm, the unevenness of the surface of the optical fiber becomes large, so that the shape of the cross section of the optical fiber becomes large. The optical fiber deviates from the circular shape, and the positional deviation of the optical fiber easily occurs, which may adversely affect the transmission of the optical signal. The lower limit of the average roughness Ra of the roughened surface is more preferably 10 nm, and the upper limit thereof is more preferably 50 nm.

The method for forming the roughened surface is not particularly limited, but it is desirable to use a roughening solution containing fluoride. This is because a roughened surface having an average roughness Ra within the above range can be formed in a short time.

As the roughening liquid containing the above-mentioned fluoride, for example, HF aqueous solution, HF-NH ₄ F mixed liquid, NaF aqueous solution, BaF ₂ aqueous solution, KF aqueous solution, CaF ₂ aqueous solution, X is used.
Examples include eF ₂ aqueous solution. Among these, HF
A solution containing is desirable. This is because a roughened surface having a desired average roughness Ra can be formed in a short time without adversely affecting the optical fiber (deformation of the optical fiber, etc.). It is suitable for forming a roughened surface on the surface of an optical fiber.

Further, it is desirable that a coupling agent layer is formed on the surface of the optical fiber instead of the roughened surface. By forming the coupling agent layer on the surface of the optical fiber, the adhesion between the optical fiber and the adhesive is improved. The coupling agent layer formed on the surface of the optical fiber may be formed so as to follow the shape of the roughened surface after forming the roughened surface on the surface of the optical fiber. It is because the effect of forming the coupling agent layer and the effect of forming the roughened surface can be obtained.

Further, in the optical fiber arrays 100 and 102, the optical fiber ribbon from which the coating resin layer at one end is removed is housed in the substrate, but a plurality of optical fibers are housed in the groove of the substrate. It may be a single-core optical fiber or a laminated optical fiber ribbon in which a plurality of optical fiber ribbons are stacked. When a laminated optical fiber ribbon is used, a plurality of optical fibers can be arranged in high density in parallel in the groove of the substrate.

FIG. 3A is a partial perspective view schematically showing an example of an optical fiber array of the present invention using a laminated optical fiber ribbon, and FIG. 3B is a sectional view taken along line AA of FIG. It is a figure. As shown in FIG. 3, in the optical fiber array 200, the optical fibers 235 and 245 exposed at one end of the laminated optical fiber ribbon 210 are housed in the V groove 257 on the substrate 251 via the adhesive 259, and the laminated optical fiber A part of the ribbon 210 is covered with the coating resin layer, and the coating resin layer holding portion 258
Held in. Although not shown, a coupling agent layer is formed on at least the surface of the V groove 257, and an adhesive layer 259 ′ is formed around the coating resin layer held by the coating resin layer holding portion 258. ing.

In the laminated optical fiber ribbon 210, two optical fiber ribbons 230 and 240 each having an exposed optical fiber at one end are stacked, and the exposed optical fiber 245 of the lower optical fiber ribbon 240 and the upper optical fiber 245 of the upper optical fiber ribbon 240 are stacked. The exposed optical fibers 235 of the optical fiber ribbon 230 are alternately arranged.

In the laminated optical fiber ribbon 210,
The exposed optical fibers 235, 245 are arranged so that the exposed optical fibers 235, 245 are arranged at the same height.
Each is bent in part. In the laminated optical fiber ribbon 210, the upper optical fiber ribbon 2
Although the exposed optical fibers 235 of 30 and the exposed optical fibers 245 of the lower optical fiber ribbon 240 are partly bent, both optical fibers can be arranged at the same height. If so, only the exposed optical fiber of the upper optical fiber ribbon may be bent, or only the exposed optical fiber of the lower optical fiber ribbon may be bent.

In the laminated optical fiber ribbon 210, it is desirable that the upper optical fiber ribbon 230 and the lower optical fiber ribbon 240 are fixed to each other with an adhesive or the like. This is because the positional deviation of the optical fibers arranged in parallel at high density is less likely to occur. Also,
Also in this optical fiber array 200, when the coating resin layer holding portion is formed together with the groove on the upper surface of the substrate, the boundary between the groove forming surface and the coating resin layer holding portion is lowered toward the coating resin layer holding portion. A wall surface having an inclination is desirable, and instead of the coating resin layer holding portion, a recess for accommodating the optical fiber together with the coating resin layer may be formed.

Further, as described above, in the optical fiber array of the present invention, the optical fibers are accommodated in the groove via the adhesive, and the lid having the above-mentioned recess is formed. An adhesive is also filled in the gap between the recess and the optical fiber, and the substrate and the outer edge of the lid are adhered via the adhesive. Further, when the coated resin layer holding portion is formed on the substrate, the optical fiber is fixed to the coated resin layer holding portion together with the coated resin layer via the adhesive layer. This adhesive layer is preferably composed of the same components as the above adhesive.

Examples of the adhesive include a cured product of a resin composition containing at least one of a thermoplastic resin, a thermosetting resin, and a photosensitive resin. Among these, a cured product of a resin composition containing a thermosetting resin or a photosensitive resin is desirable. Examples of the thermosetting resin include epoxy resin, phenol resin, silicone resin, polyimide resin, and fluororesin.

Examples of the epoxy resin include bisphenol type epoxy resin and novolac type epoxy resin. The use of the above bisphenol type epoxy resin is desirable in that the viscosity can be adjusted by selecting an A type or F type resin without using a diluting solvent, and it is preferable to adjust the viscosity to a lower value. The bisphenol F type epoxy resin is more preferable in that it can be obtained. Further, it is preferable to use the above novolac type epoxy resin because the resin has high strength, excellent heat resistance and chemical resistance, and is less likely to be thermally decomposed. Further, as the novolac type epoxy resin, a phenol novolac type epoxy resin and a cresol novolac type epoxy resin are desirable.

It is desirable that the bisphenol type epoxy resin and the novolac type epoxy resin are mixed and used. In this case, the mixing ratio of the bisphenol type epoxy resin and the novolac type epoxy resin is preferably 1: 1 to 1: 100. This is because mixing within this range can suppress an increase in viscosity.

Further, as the above-mentioned photosensitive resin, for example,
Examples thereof include resins obtained by imparting photosensitivity to the thermosetting resin. Specifically, for example, the one in which the thermosetting group of the thermosetting resin is (meth) acrylated by using (meth) acrylic acid or the like can be mentioned. Among these, the (meth) acrylate of the epoxy resin is preferable, and the epoxy resin having two or more epoxy groups in one molecule is more preferable.
Examples of the photosensitive resin also include acrylic resin and the like. These photosensitive resins may be used alone or in combination of two or more.

As the above-mentioned adhesive, for example, a cured product of an epoxy-based or acrylate-based UV-curable resin composition can be used. As will be described later, when manufacturing an optical fiber array, if uncured adhesive is poured into the gap between the optical fiber and the groove or the gap between the optical fiber and the lid, uncured adhesive will adhere to the gap due to surface tension. Although the agent will be filled, in the ultraviolet curable resin composition, since it is possible to more reliably fill the gap between the optical fiber and the groove, the cured product of the ultraviolet curable resin composition Positional deviation does not occur in the optical fiber fixed via the optical fiber. Further, the cured product of the epoxy-based or acrylate-based ultraviolet curable resin composition can also be used as an adhesive for fixing the coating resin layer to the coating resin layer holding portion. Moreover, it is desirable that a part of the cured product of the ultraviolet curable resin composition is fluorinated. By fluorinating, it is difficult for water to be generated by the cured adhesive, and the moisture resistance is improved. In addition, insulation, heat resistance, chemical resistance, etc. are also improved.

Specific examples of the above epoxy-based UV-curable resin composition include, for example, Optodyne UV-1000, Optodyne UV-1100, manufactured by Daikin Industries, Ltd.
Optodyne UV-2100, Optodyne UV-31
00, Optodyne UV-3200, Optodyne UV
-4000 etc. are mentioned.

Specific examples of the acrylate-based UV-curable resin composition include, for example, Optodyne UV-2.
000, Optodyne UV-3000 and the like.
Specific examples of the acrylate-based UV curable resin composition include, for example, 40 to 50% by weight of acrylate oligomer, 1 to 10% by weight of vinyl ester resin, and 45.
-55 wt% acrylate-based monomer, and 1-
Those containing 10% by weight of a polymerization initiator are also included.

Further, it is desirable that a part of the acrylate oligomer or the acrylate-based monomer is fluorinated. Thus, when a part of the components contained in the ultraviolet curable resin composition is fluorinated,
Since the ultraviolet curable resin composition has excellent translucency, the entire resin composition will be cured in a short time upon irradiation with ultraviolet rays.

When a cured product of the above ultraviolet curable resin composition is used as the adhesive, both the adhesive for fixing the exposed optical fiber and the adhesive for fixing the optical fiber together with the surrounding coating resin layer are used. A cured product of an epoxy-based or acrylate-based UV-curable resin composition may be used, or a cured product of an epoxy-based UV-curable resin composition may be used as an adhesive for fixing an exposed optical fiber. A cured product of an acrylate-based UV-curable resin composition may be used as an adhesive agent for fixing the resin together with the surrounding coating resin layer.

By using a cured product of a relatively hard epoxy-based UV-curable resin composition as an adhesive for fixing the exposed optical fiber, positional deviation of the optical fiber is less likely to occur, and the optical fiber coating resin By using a cured product of a relatively soft acrylate-based UV-curable resin composition as an adhesive for fixing the layers together, the coating resin layer portion should be deformed to some extent according to the shape of the portion to which the optical fiber array is attached. Will be possible. It should be noted that when a lid having a shape covering the entire surface of the substrate is attached, it is desirable to use one kind of adhesive.

When the cured product of the ultraviolet curable resin composition is used as the adhesive, the viscosity of the ultraviolet curable resin composition at 25 ° C. is not particularly limited, but it is 2
It is desirable that it is from 00 to 2000 mPa · s. If the viscosity is less than 200 mPa · s, the viscosity is too low, so that the UV curable resin composition poured into the gap between the groove and the optical fiber may flow out before curing.
If it exceeds 00 mPa · s, the gap between the groove and the optical fiber may not be reliably filled.

Further, 25 of the above ultraviolet curable resin composition
The viscosity at 0 ° C. is such that the viscosity of the ultraviolet curable resin composition used for fixing the exposed optical fiber is 200 to 20.
00 mPa · s, and the viscosity of the ultraviolet curable resin composition used for fixing the optical fiber together with the coating resin layer is 5
It is also desirable that the pressure is 000 to 30,000 mPa · s.
By using a resin composition having a viscosity in the above range as the ultraviolet curable resin composition for fixing the optical fiber, the resin composition is reliably filled in the gap between the optical fiber and the groove, When a resin composition having a viscosity in the above range is used as the ultraviolet curable resin composition for fixing the fiber together with the resin composition, it is easy to apply the resin composition around the coating resin layer. The viscosity of the ultraviolet curable resin composition may be adjusted by adjusting the blending amount of the solvent and various additives.

As the adhesive for fixing the optical fiber together with the coating resin layer, instead of the cured product of the acrylate-based UV-curable resin composition, or the acrylate-based UV-curable resin composition. A silicone adhesive may be used in combination with the cured product. As the silicone-based adhesive, for example, manufactured by Shin-Etsu Chemical Co.,
KJC-7806, Dow Corning 734, etc. are mentioned.

The above-mentioned adhesive may contain additives such as a curing agent, resin particles, inorganic particles, particles such as metal particles, a brightening agent, a reaction stabilizer, and a photopolymerization agent, if necessary. By including these additives, it is possible to improve the fluidity and adjust the degree of curing. The curing agent is not particularly limited, and commonly used curing agents can be used, and specific examples thereof include an imidazole curing agent and an amine curing agent.

Examples of the resin particles include thermosetting resins, thermoplastic resins and the like. Specifically, for example, amino resins (melamine resin, urea resin,
(Guanamine resin), epoxy resin, phenol resin, phenoxy resin, polyimide resin, polyphenylene resin,
Examples include polyolefin resins, fluororesins, bismaleimide-triazine resins, and the like. These may be used alone or in combination of two or more. Also,
As the resin particles, particles made of rubber such as acrylonitrile-butadiene rubber and polychloroprene rubber can also be used.

Examples of the inorganic particles include aluminum compounds such as alumina and aluminum hydroxide, calcium compounds such as calcium carbonate and calcium hydroxide, potassium compounds such as potassium carbonate, magnesium compounds such as magnesia, dolomite, and basic magnesium carbonate. Examples thereof include silicon compounds such as silica and zeolite, titanium compounds such as titania, and the like. These may be used alone or in combination of two or more, and as the above-mentioned inorganic particles, phosphorus or a phosphorus compound may be used.

Examples of the metal particles include gold, silver,
Examples include copper, tin, zinc, stainless steel, aluminum, nickel, iron and lead. These may be used alone or in combination of two or more. By including these particles, adjustment of the thermal expansion coefficient and improvement of flame retardancy can be achieved.

The adhesive may contain a solvent or may not contain a solvent at all. When a solvent is included, examples of the solvent include NMP.
(Normal methyl pyrrolidone), DMDG (diethylene glycol dimethyl ether), glycerin, cyclohexanol, cyclohexanone, methyl cellosolve, methyl cellosolve acetate, methanol, ethanol,
Examples include butanol and propanol.

Further, in the optical fiber array of the present invention, as an adhesive for fixing the optical fiber in the groove, an adhesive for attaching the lid to the substrate, and an adhesive for fixing the coating resin layer to the coating resin layer holding portion. Instead of the cured product of the resin composition as described above, solder may be used. When solder is used as the adhesive, it is desirable to previously form a metal layer on the portion that contacts the solder. This is because the adhesion is improved.

The optical fiber array of the present invention having such a structure can be manufactured, for example, by the method of manufacturing the optical fiber array of the present invention described below.

Next, a method for manufacturing the optical fiber array of the present invention will be described. The method of manufacturing an optical fiber array of the present invention is characterized by including at least the following steps (A) to (D). (A) A groove forming step of forming a plurality of grooves on a part of the upper surface of the substrate, (B) a coupling agent layer forming step of forming a coupling agent layer on at least the surface of the groove, and (C) an optical fiber in the groove. Optical fiber storing step for storing
(D) An adhesive filling step of filling an uncured adhesive into the optical fiber non-enclosed portion of the groove.

Since the method for producing an optical fiber array of the present invention includes a coupling agent layer forming step of forming a coupling agent layer on the surfaces of a plurality of grooves formed on at least a part of the upper surface of the substrate, at least the above-mentioned grooves are formed. A coupling agent layer can be formed on the surface. Since the surface of the groove in which such a coupling agent layer is formed is excellent in adhesiveness with the adhesive, in the optical fiber array manufactured by the method for manufacturing an optical fiber array of the present invention, the surface of the groove and the adhesive are In the optical fiber array, peeling does not occur between the
The optical signal can be accurately transmitted. In addition, in the method for producing an optical fiber array of the present invention, since the coupling agent layer is formed on the surface of the groove in the coupling agent layer forming step, the end surface of the groove is not yet removed in the adhesive filling step described later. When the cured adhesive is poured, the uncured adhesive is evenly poured into the gap between the groove and the optical fiber, and voids or the like do not occur in the cured adhesive.

The method of manufacturing the optical fiber array of the present invention will be described below in the order of steps. (1) Using the above-mentioned substrate made of silicon or the like as a starting material, first, the step (A), that is, the groove forming step of forming a plurality of grooves on a part of the upper surface of the substrate is performed. Specifically, for example, the groove can be formed on the upper surface of the substrate by going through the following steps (i) to (vi). 4 (a)-
(F) is a sectional view showing an example of a method for forming a groove in a substrate.

(I) First, the mask layer 15 is formed on the substrate 151.
2 (152a, 152b) are formed (see FIG. 4A). The number of mask layers is not limited to two as shown in FIG. 4 and may be one or three or more.

As a method of forming the mask layer 152,
For example, a method of forming a thin film by sputtering, CVD, plating or the like, a method of forming an oxide film by thermal oxidation or the like, a method combining these, or the like can be used. Among these, for example, when forming a mask layer on a substrate made of silicon, first an oxide film (SiO ₂ film) is formed by thermal oxidation, and then a thin film is formed on this oxide film by CVD. A method of forming is desirable. By forming such a mask layer, it is possible to form a mask having an arbitrary shape by subjecting an arbitrary portion to etching treatment in a later step.

(Ii) Next, a resist resin layer 154 is formed on the mask layer 152 (see FIG. 4B). Specifically, a method in which a resist resin composition whose viscosity has been adjusted in advance is applied by a spin coater, a curtain coater, a roll coater, printing, or the like, or a resist resin film which has been formed into a film shape in advance is attached. A method of attaching can be used.

The resin composition for resist or the resin film for resist is composed of, for example, a resin component and a curing agent, particles, a rubber component, an additive, a reaction stabilizer, a solvent and the like which are blended as necessary. There are things. Examples of the resin component include a thermosetting resin, a thermoplastic resin, a photosensitive resin, a resin in which a part of the thermosetting resin is replaced with a photosensitive group, a composite resin of these, and the like.

Specifically, for example, thermosetting resins such as epoxy resin, phenol resin, polyimide resin, bismaleimide resin, polyphenylene resin, polyolefin resin, fluororesin; thermosetting groups of these thermosetting resins (for example, , (Epoxy group in epoxy resin) is reacted with methacrylic acid or acrylic acid to form an acrylic group (photosensitive group).
Resins provided with: thermoplastics such as phenoxy resin, polyether sulfone (PES), polysulfone (PSF), polyphenylene sulfone (PPS), polyphenylene sulfide (PPES), polyphenyl ether (PPE), and polyetherimide (PI) Resin: Acrylic resin, photosensitive resin such as ultraviolet curable resin, and the like. Among these, epoxy resin, phenol resin, polyimide resin, acrylic resin, and ultraviolet curable resin are preferable. This is because when the mask layer under the resist resin layer is treated with an etching solution in a later step, the resistance to the etching solution is excellent. Examples of the curing agent include imidazole curing agents, amine curing agents, acid anhydride curing agents, and the like.

The thickness of the resist resin layer is 10
˜50 μm is desirable. The resist resin layer may be in a cured state or a semi-cured state. Specifically, for example, in the case where the resist resin layer in the portion corresponding to the groove to be formed on the substrate is removed by exposure and development in a later step, it is preferably in a semi-cured state. When the resist resin layer corresponding to the groove is removed, it may be in a cured state or a semi-cured state. In the case of forming a resist resin layer in a completely cured state or a semi-cured state, it is desirable to perform the curing treatment by heating at 70 to 200 ° C, for example. Moreover, you may perform step hardening which changes a heating temperature step by step.

(Iii) Next, a part of the resist resin layer 154, that is, a part corresponding to a groove formed in the substrate 151 is removed to form an etching resist 155 (FIG. 4).
(See (c)). The resist resin layer 154 can be removed by, for example, exposure and development treatment. Specifically, for example, a mask is placed on the semi-cured resin layer for resist, an exposure process is performed, and then a development process using a chemical solution such as an alkaline solution or an organic solvent is performed. The developing treatment can be performed by immersing the substrate having the resin layer for resist in the chemical solution or spraying the chemical solution. As the mask, it is possible to use a mask in which a groove pattern is drawn in a portion corresponding to the removed portion of the resist resin layer.

The removal of the resist resin layer 154 is
Alternatively, laser processing may be used. Examples of the laser used for the laser processing include carbon dioxide gas laser, excimer laser, UV laser, and YAG laser.
These lasers may be selectively used in consideration of the shape of the removed portion of the resist resin layer, the composition of the resist resin layer, and the like. By adjusting the shape of the etching resist formed in this step, it is possible to adjust the shape of the groove formed through the subsequent steps.

(Iv) Next, the mask layer 152 exposed in the portion where the etching resist 155 is not formed is removed, and the substrate 151 is removed.
A mask 156 is formed by exposing a portion where the groove is formed (see FIG. 4D). The mask layer 152 can be removed by, for example, plasma treatment using oxygen plasma or nitrogen plasma, corona treatment, or dry etching treatment such as reverse sputtering. Specifically, for example,
This can be performed by irradiating the mask layer with oxygen plasma under vacuum or reduced pressure. By performing such a dry etching process, it is possible to selectively remove only the mask layer in the resist non-forming portion without causing damage or deformation of the etching resist.

The mask layer 152 can be removed by, for example,
It is also performed by immersing the substrate on which the mask layer 152 is formed in an etching solution or an acid solution, immersing the substrate in the solution and performing ultrasonic treatment, or spraying the etching solution or the acid solution on the mask layer. be able to. The removal method to be specifically selected may be appropriately determined in consideration of the material and thickness of the mask layer. For example, when the mask layer is made of an oxide film, plasma treatment or etching solution is used. When the mask layer is made of a metal layer, reverse sputtering or a treatment with an etching solution may be selected.

(V) Next, the etching resist 155 is peeled and removed (see FIG. 4E). The removal of the etching resist 155 should be carried out using an alkaline solution such as NaOH, KOH, an acid solution such as sulfuric acid, acetic acid, carbonic acid, alcohols such as methanol and ethanol, amines, ketones, organic solvents such as acetone, and the like. You can This allows
Only the mask 156 having the opening corresponding to the portion where the groove is formed is formed on the substrate 151.

(Vi) Next, the groove 157 is formed in the substrate 151 (see FIG. 4F). The groove 157 is, for example, the substrate 1
It can be formed by spraying an etching solution on 51 through the mask 156 or by immersing the substrate 151 on which the mask 156 is formed in the etching solution. Examples of the etching solution include NaOH and K
An alkali such as OH, an acid such as nitric acid, phosphoric acid, sulfuric acid, a fluorine-based compound such as hydrogen fluoride or bromine fluoride, a halide, a hydrogen peroxide solution, an alcohol such as methanol or ethanol, or the like can be used. When the groove is formed by using these etching solutions, the cross-sectional shape of the groove is V-shaped, inverted trapezoidal shape, rectangular shape, or a combination thereof.

The concentration of the etching solution is preferably 10 to 50% by weight. If the concentration is less than 10% by weight, the etching process may take a long time, while if it exceeds 50% by weight, the etching rate hardly changes.
The temperature of the etching solution is preferably 20 to 90 ° C., and the etching rate is preferably 0.5 to 5.0 μm / min. If the temperature of the etching solution is lower than 20 ° C., the etching may not be sufficiently performed, and even if the temperature of the etching solution exceeds 90 ° C., the etching amount is hardly changed, and the safety during the work is lowered.

Here, when the groove is formed in the substrate whose material is silicon or gallium arsenide, it is desirable to perform the etching treatment using an alkaline solution such as KOH. When a substrate made of silicon or gallium arsenide is subjected to etching treatment, a groove having a desired shape is formed by selecting an appropriate etching surface, type of etching solution, and shape of the etching resist non-forming portion. be able to.

That is, when a silicon substrate is etched using an etching solution containing KOH, the (100) plane of the silicon substrate is preferentially etched as compared with the (111) plane and the (110) plane, and each crystal is crystallized. Since the etching rate ratio of the surface is almost constant, a groove having a desired shape can be formed. Specifically, when the (100) surface of the silicon substrate is subjected to etching treatment, it is possible to form a groove having a V-shaped or inverted trapezoidal cross section.
When the (110) plane is subjected to etching treatment, a groove having a rectangular cross section can be formed.

When the gallium arsenide substrate is etched using an etching solution containing KOH, (11
1) The slowest etching rate of Ga surface is (111) A
By utilizing the fact that the s-plane has the highest etching rate, it is possible to form a groove having a desired shape.

When performing the etching treatment in this step, a surfactant or the like may be added to the etching solution. When the foaming occurs violently during the etching process, irregularities may be formed on the etching surface due to the foaming, but by adding a surfactant, the foaming during the etching process can be suppressed. Also,
The etching process may be performed while applying ultrasonic waves. This is because foaming can also be suppressed by applying ultrasonic waves.

When the substrate is dipped in the etching solution to perform the etching process, the etching process may be performed while the substrate is swung or the etching solution is stirred. Through the steps (i) to (vi), a groove having a desired shape can be formed on the substrate.

When the groove is formed in the substrate through the above steps (i) to (vi), the mask formed on the substrate is not particularly removed in this forming step. Strictly speaking, the portion to be accommodated is a portion in which the mask non-forming portion and the groove provided on the substrate are combined, but after the groove is formed on the substrate in the present specification, unless otherwise specified, both of these are formed. The combined part is called a groove.

Further, in the step (1), it is desirable to form a groove in the substrate and to form a coating resin layer holding portion for holding the optical fiber or the optical fiber ribbon together with the coating resin layer. The method for forming the coated resin layer holding portion is not particularly limited, and examples thereof include a method using a device equipped with a diamond blade. Further, the formation of the coating resin layer holding portion may be performed once or may be performed twice or more.

When the coating resin layer holding portion is formed, the upper surface of the coating resin layer holding portion may have irregularities. In this case, a polishing process may be performed to flatten the unevenness, but if the unevenness is such that the optical fiber ribbon is greatly inclined when holding the optical fiber ribbon or the like, the polishing process is particularly performed. It is desirable to leave it as it is. This is because when the coating resin layer holding portion holds the coating resin layer via the adhesive, the adhesion between the coating resin layer holding portion and the adhesive is improved due to the anchor effect. Further, when forming the coated resin layer holding portion here, even if a plurality of holding surfaces having different heights are formed in the coated resin layer holding portion so as to follow the shape of the optical fiber ribbon or the like to be held. Good.

When forming the coating resin layer holding portion together with the groove on the upper surface of the substrate, the boundary between the groove forming surface and the coating resin layer holding portion is the coating resin layer holding portion as shown in FIG. It is desirable that the wall surface has a slope that descends. This is because the load on the optical fiber can be reduced. Further, instead of the coating resin layer holding portion,
You may form the recessed part which can accommodate the optical fiber with the coating resin layer of the circumference | surroundings. The concave portion can also be formed by using a device equipped with a diamond blade.

(2) Next, the step (B), that is, the coupling agent layer forming step of forming the coupling agent layer on at least the surface of the groove is performed.

By carrying out such a coupling agent layer forming step, the affinity (adhesion) between at least the surface of the groove formed in the substrate and the adhesive to be filled in the subsequent step can be improved. Specifically, a coupling agent layer can be formed on the surface of the groove, and the surface condition of the groove can be made uniform.

As a method of forming the coupling agent layer on the surface of the groove, for example, a method of immersing the grooved substrate in a solution containing the coupling agent can be used. The lower limit of the temperature of the solution is preferably 20 ° C, and the upper limit thereof is preferably 50 ° C.
If the temperature of the solution is lower than 20 ° C, the coupling agent is hard to adhere to the surface of the substrate (the surface of the groove), while if it exceeds 50 ° C, the coupling agent may be decomposed. The lower limit of the temperature of the solution is more preferably 25 ° C, and the upper limit thereof is more preferably 35 ° C.

Instead of immersing the substrate in the solution containing the coupling agent, a method of spraying or applying the solution onto the surface of the substrate (the surface of the groove) can be used. Further, in this step, it is desirable to form the coupling agent layer not only on the surface of the groove formed in the substrate, but also on the portion of the upper surface of the substrate that faces the lid portion including the groove and the entire upper surface of the substrate.

Further, in the groove forming step, when the groove is formed on the substrate by passing through the steps (i) to (vi), as described above, the etched portion and the mask non-formation are formed. The part where the part and the part are combined becomes a groove. Therefore, in this case, the surface of the groove in which the coupling agent layer is formed corresponds to the portion where the portion exposed by the etching process and the wall surface of the mask are combined.

Therefore, as described above, when the coupling agent layer is formed on the wall surface of the groove, the coupling agent to be used and the processing conditions may be appropriately selected in consideration of the material of the wall surface of the groove. desirable. Further, even when the coupling agent layer is formed on the entire surface of the substrate including the surface of the groove, the mask remains on the groove non-forming portion on the upper surface of the substrate, and the groove non-forming portion and the wall surface of the groove exposed by etching. However, in this case as well, it is desirable to appropriately select the coupling agent to be used and the processing conditions in consideration of the material of the groove non-forming portion on the upper surface of the substrate and the wall surface of the groove.

Before the step (B), at least the surface of the groove is preferably subjected to plasma treatment and / or oxidation treatment.

Examples of the plasma treatment include a method using at least one selected from oxygen, nitrogen, carbon dioxide, argon, carbon tetrachloride, carbon tetrafluoride and the like. Among these, the method using oxygen is desirable. This is because the substrate can be processed at low cost without damaging the substrate. Further, it is desirable that the plasma treatment is performed not only on the surface of the groove but also on the entire surface of the substrate.

Further, the plasma radiation amount in the above plasma treatment is preferably 200 to 1000 W. If the plasma radiation amount is less than 200 W, the surface condition of the groove may not be sufficiently improved, while if the plasma radiation amount exceeds 1000 W, the substrate may be damaged. Further, the gas supply amount in the plasma processing is 100 to 500 sec. / M is desirable, and the treatment time is preferably 1 to 20 minutes. If the treatment time is less than 1 minute, the surface condition of the groove may not be sufficiently improved, while if the treatment time is longer than 20 minutes, the effect of improving the surface condition is almost unchanged. Further, it is desirable that the plasma treatment be performed under vacuum or reduced pressure.

Examples of the oxidization treatment include an oxidization treatment using a mixed solution of sulfuric acid and hydrogen peroxide, an oxidization treatment using a fuming nitric acid solution, and an oxidization treatment for heating a substrate. Further, it is desirable that the oxidation treatment is performed not only on the surface of the groove but also on the entire surface of the substrate. It should be noted that desirable conditions and the like for each of the above-mentioned oxidation treatments when the material forming the substrate is silicon will be described below, but the conditions and the like for these oxidation treatments should be appropriately adjusted according to the type of substrate to be used and the like. Becomes

In the oxidation treatment using the mixed solution of sulfuric acid and hydrogen peroxide solution, the blending amount (weight) of sulfuric acid in the mixed solution is the lower limit with respect to the blending amount (weight) of hydrogen peroxide solution. Is preferably 1 time, more preferably 4 times. The upper limit is preferably 7 times, more preferably 5 times. Further, the lower limit of the liquid temperature when processing a substrate made of silicon using the mixed liquid of sulfuric acid and hydrogen peroxide is preferably 30 ° C., and more preferably 90 ° C. Also,
The upper limit is preferably 120 ° C, and more preferably 100 ° C. In addition, the treatment time when treating with the mixed solution of the sulfuric acid and hydrogen peroxide solution is 1 to 2
5 minutes is desirable.

In the oxidation treatment using the fuming nitric acid solution, the lower limit of the concentration of the solution is preferably 1% by weight, more preferably 2% by weight. The upper limit is preferably 5% by weight, more preferably 4% by weight. The lower limit of the liquid temperature when processing a substrate made of silicon using the fuming nitric acid solution is preferably 25 ° C., and more preferably 40 ° C. The upper limit is preferably 100 ° C, more preferably 80 ° C. The processing time when processing the substrate using the fuming nitric acid solution is preferably 1 to 25 minutes.

Further, in the oxidation treatment for heating the substrate made of silicon, the lower limit of the heating temperature for heating the substrate made of silicon is preferably 200 ° C., and more preferably 400 ° C. The upper limit is preferably 600 ° C, more preferably 500 ° C. The processing time for heating the silicon substrate is preferably 1 to 30 minutes.

By oxidizing at least the surface of the groove of the substrate made of silicon under such conditions, the degree of oxidation of the surface of the groove can be set to 0.1 to 1000 nm.

When the plasma treatment and the oxidation treatment are performed in this step, both treatments are performed in this order.

Before the step (B), the portion of the substrate where the coupling agent layer is formed may be subjected to pretreatment such as cleaning treatment and acid treatment.

Examples of the cleaning treatment include alkali cleaning, acid cleaning, neutral cleaning and the like. In the above cleaning process, the surface condition of the groove can be made into a desired condition mainly by the degreasing action and the foreign substance removing action.

The alkaline cleaning may be carried out, for example, by spraying a solution prepared by adding caustic soda or an alkaline salt of silicic acid, carbonic acid, phosphoric acid or condensed phosphoric acid to an anionic surfactant and a nonionic surfactant. It can be performed by immersing the substrate in the solution. It can also be performed by an electrolytic cleaning method in which a surfactant is added.

The above-mentioned acid cleaning can be carried out by, for example, spraying a solution of a cationic surfactant added to an acid such as sulfuric acid or hydrochloric acid, or immersing the substrate in the solution.

Examples of the acid treatment include a method of immersing the grooved substrate in a solution containing at least one acid selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid and phosphoric acid. . In the above acid treatment, the concentration of acid in the solution is preferably 10% by weight or more. This is because when the acid concentration is less than 10% by weight, it takes a long time to bring the surface state of the substrate into a desired state.

The treatment time in the above-mentioned acid treatment may be appropriately selected in consideration of the type of acid used and its concentration. Generally, the lower limit is preferably 1 minute and the upper limit is 15 minutes is desirable. If the immersion time is less than 1 minute, the surface condition of the substrate may not be sufficiently improved, while if it exceeds 15 minutes, the surface condition of the substrate hardly changes.
The lower limit of the acid treatment time is more preferably 2 minutes, and the upper limit thereof is more preferably 10 minutes.
In addition, the liquid temperature of the acid solution during the acid treatment is usually preferably 20 to 40 ° C.

When the above-mentioned plasma treatment or oxidation treatment is carried out, pretreatment such as cleaning treatment or acid treatment is carried out before plasma treatment and / or oxidation treatment.

When the oxidation treatment, the plasma treatment, the cleaning treatment, the acid treatment and the like are applied to the wall surface of the groove formed on the substrate, the entire upper surface of the substrate including the wall surface of the groove, etc., the above-mentioned coupling agent is used. As in the case of forming the layer, the material of the treated portion may be different. Even in such a case, it is desirable to appropriately select the processing condition among the processing conditions described above in consideration of the material of the portion to be processed and the like.

(3) Here, apart from the production of the substrate, an optical fiber ribbon in which a part of the coating resin layer is removed and the optical fiber is exposed is produced. Here, the coating resin layer to be removed may be the coating resin layer at one end of the optical fiber ribbon or may be a portion of the coating resin layer other than both ends of the optical fiber ribbon. It is desirable that it is a part of the coating resin layer other than both end portions of. In such an optical fiber ribbon from which a part of the coating resin layer other than both ends is removed, both ends of the exposed optical fiber are fixed, so that variation in the axial direction of the optical fiber is less likely to occur, and in a post-process. This is because it is suitable for being stored in the substrate.

The above-mentioned coating resin layer is removed by, for example, a mechanical removal method using a coating resin layer peeling device such as a stripper, or a chemical removal method by dissolving the coating resin layer using an organic solvent. It can be performed using a method or the like. Alternatively, a method of removing by irradiation with laser light may be used.

After removing the coating resin layer, it is desirable to form a roughened surface on the surface of the optical fiber by the method described above. When the roughened surface is formed on the surface of the optical fiber, the degree of inflow of the uncured adhesive due to the surface tension is substantially uniform when the uncured adhesive is poured from the end surface of the substrate in the subsequent process. As a result, the uncured adhesive can be reliably poured into the gap between the groove and the optical fiber.

After removing the coating resin layer, it is desirable to form a coupling agent layer on the exposed surface of the optical fiber. The coupling agent layer can be formed by using the same method as the method of forming the coupling agent layer on the upper surface (the surface of the groove) of the substrate described above. Here, the formation of the coupling agent layer may be performed in place of the above-described formation of the coupling agent layer, or after the roughened surface is formed on the surface of the optical fiber, the shape of the roughened surface is followed. A coupling agent layer may be formed.

(4) Next, the step (C), that is, the optical fiber housing step of housing the optical fiber in the groove is performed.

Here, when housing the optical fiber ribbon from which the coating resin layer at one end has been removed, the optical fiber ribbon may be housed so that the end face of each optical fiber and the side face of the substrate are aligned. The fibers may be housed so as to protrude from the side surface of the substrate by a certain length.

Further, when the optical fiber ribbon from which a part of the coating resin layer other than both ends thereof is removed is housed, the optical fiber ribbon which has not been housed in the substrate after housing the optical fiber ribbon is housed. Will be cut off at one end. In addition, when cutting and removing one end of the optical fiber ribbon, it may be cut and removed so that the end face of each optical fiber and the side surface of the substrate are aligned, or each optical fiber has a certain length from the side surface of the substrate. You may cut and remove so that it may protrude. The cutting and removal of the optical fiber ribbon can be performed by cutting using a cutter or the like. Alternatively, mechanical polishing may be performed.

When the coating resin layer holding portion is formed in the step (1), the optical fiber is housed in the groove and the optical fiber ribbon is placed on the coating resin layer holding portion in this step. Place the coating resin layer together. Also, on the substrate,
When the concave portion for accommodating the optical fiber ribbon together with the coating resin layer is formed, the optical fiber ribbon together with the coating resin layer is accommodated in the concave portion.

(5) Next, the step (D), that is, the adhesive filling step of filling the uncured adhesive into the optical fiber non-accommodating portion of the groove is performed.

In this step, specifically, for example, the uncured adhesive is poured from the end face (end of the groove) of the substrate, and then the uncured adhesive is cured to fix the optical fiber. . Further, when forming a coating resin layer holding portion on the substrate, when mounting the optical fiber ribbon together with the coating resin layer in the coating resin layer holding portion, or when housing the optical fiber ribbon in the recess together with the coating resin layer, It is desirable that an uncured adhesive is applied around the coating resin layer and the uncured adhesive is cured to fix the coating resin layer through the adhesive layer. Here, when the shape of the coating resin layer holding portion is a shape including a wall surface having an inclination, in the coating resin layer holding portion, a part of the exposed optical fiber,
It is desirable to fix the coating resin layer through the adhesive layer. In addition, before storing the optical fiber, an uncured adhesive may be poured into the groove or the like in advance, and after storing the optical fiber, the adhesive may be cured to fix the optical fiber.

Further, in the above-mentioned process, since the coupling agent layer is formed on at least the surface of the groove formed in the substrate, the surface of the groove has a high affinity with the uncured adhesive. ing. Therefore, when the uncured adhesive is poured in this step, the adhesive is surely poured into the groove, and voids or the like do not occur in the adhesive after the curing treatment.

The uncured adhesive is cured by, for example, 8
It can be performed by heating at 0 to 250 ° C.
The adhesive containing the photosensitive resin may be cured by irradiating it with ultraviolet rays or infrared rays.

Further, it is desirable that after the exposed optical fiber of the optical fiber ribbon is housed and fixed, a lid portion is formed to cover the part of the exposed optical fiber housed in the groove. As described above, the shape of the lid portion may be a flat plate shape or the like, but a concave portion for collectively storing the optical fibers not accommodated in the groove is formed on the surface facing the substrate. It is desirable that the shape is a predetermined shape. Here, when forming the lid, it is desirable to previously form a coupling agent layer on the surface of the lid facing the substrate.
This is because the adhesion with the adhesive is improved, and the degree of inflow of the uncured adhesive becomes uniform when the uncured adhesive is filled. As the method of forming the coupling agent layer on the surface of the lid portion facing the substrate, the same method as the method of forming the coupling agent layer on the surface of the groove of the substrate can be used.

Further, when the lid is made of an inorganic material or a metal material, the recess may be formed by cutting a plate-like body made of these, and the lid is made of an organic material. In this case, after molding the organic material into a plate-like body, it is subjected to exposure and development treatment or laser treatment, or
It may be performed by subjecting a plate-shaped body made of a completely cured organic material to cutting processing.

When the lid is formed, the uncured adhesive is poured into the gap between the lid and the optical fiber,
It is desirable to fix the lid and the optical fiber by curing the uncured adhesive. Further, after housing the optical fiber in the groove of the substrate and before fixing the optical fiber in the groove, the lid is formed first, and then the gap between the groove and the optical fiber, and the recess and the optical fiber It is desirable to pour uncured adhesive into the gap at the same time. This is because when the lid is placed on the adhesive after the adhesive is applied, air easily enters between the adhesive and the lid. When a photosensitive resin is used as the adhesive, ultraviolet rays or infrared rays are radiated through the lid. Therefore, as described above, the material of the lid is quartz, glass, or the like. It is desirable that the material transmits the ultraviolet rays and infrared rays. Further, in the process, solder paste may be filled instead of the uncured adhesive, and then reflow treatment may be performed to fix the optical fiber, the lid, and the like via the solder.

In the step (4), the optical fiber ribbon from which a part of the coating resin layer other than both ends thereof is removed is accommodated, and the portion of the optical fiber ribbon which is not accommodated in the substrate is cut and removed. In this case, it is desirable that this cutting removal be performed after the lid is formed.

After storing the optical fiber ribbon with one end exposed, or after storing a part of the exposed optical fiber other than both ends and cutting and removing one end of the optical fiber ribbon. It is desirable to polish the end surface of the optical fiber. Here, when performing the polishing treatment, it is desirable to perform the polishing treatment so that the end faces of the optical fiber, the substrate and the lid are inclined. This is because it is possible to suppress the generation of return light when transmitting an optical signal. In this case, while polishing the end face of the optical fiber,
The side surface of the substrate or the lid may be polished.

Through the above steps, the optical fiber array of the present invention can be manufactured. Although the method of manufacturing the optical fiber array using the optical fiber ribbon has been described here, the optical fiber array of the present invention can be manufactured by using a single-core optical fiber or a laminated optical fiber ribbon. be able to.

Specifically, when an optical fiber array is manufactured by using a single-core optical fiber, for example, a plurality of optical fibers from which the coating resin layer at one end is peeled off are arranged in parallel using an aligner. Then, in the step (4), the optical fiber is stored in the substrate while being held by the aligner, and then the optical fiber is fixed and the lid is formed by the same method as the above method. Thus, the optical fiber array can be manufactured.

When an optical fiber array is manufactured using the laminated optical fiber ribbon, for example, a laminated optical fiber ribbon 300 in which a part of the coating resin layer is removed is prepared as shown in FIG. After that, the optical fiber array can be manufactured by housing and fixing this laminated optical fiber ribbon on the substrate. FIG. 5 is a partial perspective view schematically showing an embodiment of the laminated optical fiber ribbon.

As shown in FIG. 5, the laminated optical fiber ribbon 300 has a part of the optical fibers 345a other than both ends thereof.
Between the exposed optical fibers 345a of the exposed second optical fiber ribbon (lower optical fiber ribbon) 340,
The first optical fiber ribbon 330 and the second optical fiber 330 are arranged so that the exposed optical fiber 335a of the first optical fiber ribbon (upper optical fiber ribbon) 330 with the optical fiber 335a at one end thereof exposed. Ribbon 340
And are stacked.

In the laminated optical fiber ribbon 300,
The exposed optical fibers 335a, 345a are arranged so that the exposed optical fibers 335a, 345a are arranged at the same height.
Each of 5a is bent at a part thereof. Thus, optical fiber 335a and optical fiber 345a
By arranging the same at the same height, it becomes a shape suitable for being housed in the groove of the substrate.

In the laminated optical fiber ribbon 300,
The exposed optical fiber 3 of the first optical fiber ribbon 330
35a and a part of each of the exposed optical fibers 345a of the second optical fiber ribbon 340 are bent, but if both optical fibers can be arranged at the same height, Only the exposed optical fiber of the optical fiber ribbon may be bent, or only the exposed optical fiber of the second optical fiber ribbon may be bent.

Further, in the laminated optical fiber ribbon 300, it is desirable that the first optical fiber ribbon 330 and the second optical fiber ribbon are fixed by an adhesive. Note that in the laminated optical fiber ribbon 300 shown in FIG. 5, eight optical fibers are arranged at the same height, but the number of optical fibers in the laminated optical fiber ribbon is not limited to eight, and seven optical fibers are provided. May be less than or equal to 9
It may be more than a book. Further, the number of optical fibers in each of the first and second optical fiber ribbons is as shown in FIG.
It is preferable that the number of the first optical fiber ribbons is one, or that of the second optical fiber ribbons is one. This is because in such a case, the optical fibers can be arranged at the highest density.

In the production of the laminated optical fiber ribbon, for example, first, the coating resin layer at one end of the optical fiber ribbon is
As described above, a method of using the coating resin layer peeling device, a method of dissolving with an organic solvent, a method of irradiating with a laser beam and the like to produce a first optical fiber ribbon by removing it, apart from this, A second optical fiber ribbon is produced by removing a part of the coating resin layer other than both end portions of the optical fiber ribbon by using the same method for removing the coating resin layer as described above. After bending the part, the first and second optical fiber ribbons may be stacked with an adhesive so that the two optical fibers are alternately arranged at equal intervals.

As a method for accommodating and fixing such a laminated optical fiber ribbon on a substrate, the same methods as those used in the steps (4) and (5) can be used. Even when an optical fiber array is manufactured using the laminated optical fiber ribbon, after the laminated optical fiber ribbon is housed and fixed in the substrate, the second optical fiber ribbon is cut off and the end face of the optical fiber is removed. And the like.

[0152]

The present invention will be described in more detail below.

(Example 1) A. Fabrication of an optical fiber ribbon from which a part of the coating resin layer has been removed.
Optical fiber ribbons (Sumitomo Electric Industrial Co., Ltd.) in which eight fibers of 50 μm are arranged in parallel, and a coating resin layer (primary coating layer 113 and secondary coating layer 114) made of an acrylate-based ultraviolet curable resin is coated around the optical fibers. Made),
A coating resin layer (primary coating layer and secondary coating layer) at a portion 5 to 50 mm from one end of this optical fiber ribbon
Was peeled off by a coating resin layer peeling device (see FIG. 6 (a)).

B. Manufacture of lid part A substrate made of quartz glass is cut using a device equipped with a diamond blade to form a recess 161 for accommodating an exposed optical fiber.
(See FIG. 7A). The recess has a rectangular cross section.

C. Fabrication of optical fiber array (1) Thickness 0.5-2.0 with polishing treatment on its surface
A silicon substrate 151 having a size of mm was used as a starting material, and a mask layer 152 was formed on the silicon substrate 151 by the following method (see FIG. 4A). That is, first, the surface of the silicon substrate 151 by thermal oxidation furnace to form a SiO ₂ film 152a having a thickness of 0.04 .mu.m, then using a vacuum CVD method on this SiO ₂ film, a thickness of 0. 1 μm Si ₃ N ₄
The SiO ₂ film 152a is formed by forming the film 152b.
And a Si ₃ N ₄ film 152b as a mask layer 15 composed of two layers.
Formed 2.

(2) Next, a thickness of 2 is formed on the mask layer 152.
A resin layer for resist 154 was formed by sticking a resin film for resist of 5 μm (see FIG. 4B).

(3) Next, the resist resin layer 154 is formed.
Place a mask with a groove pattern drawn on it, 800m
It is exposed to J / cm ² and then developed with an alkaline solution to form an etching resist 15 on the mask layer.
5 was formed (see FIG. 4 (c)).

(4) Next, the etching resist 155
The mask layer exposed in the formation part is removed by the following method,
A mask 156 was formed by exposing a part of the substrate 151.
(See FIG. 4 (d)). That is, first, the exposed Si_Three
N_FourDry etching of the film using oxygen plasma
SiO by removing with_TwoExpose the membrane and
And this SiO _TwoThe film was cleaned using an HF-based etching solution.
Etching process to remove and expose the silicon substrate.
I let it out.

(5) Next, the etching resist was peeled and removed using a 10 wt% NaOH aqueous solution (FIG. 4).
(See (e)). As a result, on the silicon substrate 151, only the mask 156 having the opening corresponding to the portion where the groove is formed is formed.

(6) Next, the silicon substrate 151 on which the mask 156 is formed is subjected to a KOH concentration of 25% by weight and a liquid temperature of 7%.
8 ° C. etching solution (KOH: 100 g, H ₂ O: 30
0 g) to form eight V-grooves having a depth of 120 μm (see FIG. 4 (f)). Then the substrate 15
A coating resin layer holding portion 158 (see FIG. 6A) for holding the optical fiber ribbon together with the coating resin layer on a part of the
It was formed by performing a cutting process using a device equipped with a diamond blade. Note that the substrate shown in FIG. 6 has only four grooves, but this diagram is a schematic diagram.
Actually, as described above, eight grooves were formed on the substrate.

(7) Next, a coupling agent layer was formed under the following conditions on the entire upper surface of the substrate including the surface of the groove formed in the substrate. That is, a silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., B
KM573) was slowly added to 2.0% by weight and stirred for 1 hour. The substrate was dipped in the coupling agent solution for 1 minute and then dried at 110 ° C. for 30 minutes to form a coupling agent layer on the entire upper surface of the substrate. The coupling agent layer may be formed by applying the coupling agent solution on the entire upper surface of the substrate and then drying it under the above conditions.

(8) Next, the exposed portion of the optical fiber 115 of the optical fiber ribbon 110A produced in the above A is
It is placed in the V groove 157 (see FIGS. 6A and 6B), and the lid 160 manufactured in the above B is further placed on the substrate 151 via an adhesive (UV-3000, manufactured by Daikin Industries, Ltd.). It was attached (see FIG. 7 (a)). The adhesive was previously applied to the outer edge of the lid. Furthermore, an adhesive (U, manufactured by Daikin Industries, Ltd., U manufactured by Daikin Industries, Ltd.
V-3000) was poured. Further, the adhesive (U) is also applied to the periphery of the coating resin layer placed on the coating resin layer holding portion 158.
V-3000) was applied.

Next, an ultraviolet ray of 10 J / cm ² is irradiated from the upper part of the substrate 151 provided with the lid portion 160 with a high pressure mercury lamp, and then the adhesive is heated at 60 ° C. for 1 hour. It was completely cured and the lid 160 was fixed. Further, here, by irradiating the coating resin layer holding portion with ultraviolet rays as well, a part of the exposed optical fiber and the coating resin layer are exposed to the coating resin layer holding portion via an adhesive (not shown). Fixed

(9) Next, the coating resin layer 114a not housed in the substrate at one end of the optical fiber ribbon 110A,
The optical fiber covered with the coating resin layer was cut and removed by a diamond cutter, and further, polishing treatment was performed so that the end face of the optical fiber and the end faces of the substrate and the lid portion were aligned, to manufacture the optical fiber array 102. (See FIG. 7B).

Example 2 In the step (7) of C of Example 1, the entire upper surface of the substrate including the surface of the groove formed in the substrate was subjected to oxidation treatment under the following conditions, and then the coupling agent was used. An optical fiber array was manufactured in the same manner as in Example 1 except that the layers were formed. That is, the substrate in which the groove is formed is mixed with a mixed solution of sulfuric acid and hydrogen peroxide (mixing ratio = 4: 1).
(Weight ratio), liquid temperature 95 ° C.) for 10 minutes. When the surface of the groove after the oxidation treatment was measured by ESCA, it was confirmed that an oxide film existed on the surface of the groove, and the degree of oxidation was 10 nm.

(Example 3) In the step (7) of C of Example 1, the entire upper surface of the substrate including the surface of the groove formed in the substrate was subjected to plasma treatment under the following conditions, and then the coupling agent was used. An optical fiber array was manufactured in the same manner as in Example 1 except that the layers were formed. That is, using a plasma screening device (Kyushu Matsushita Electric Co., Ltd., PC12F-G type), in a vacuum state, a plasma irradiation amount of 800 W,
Oxygen supply amount 300 sec. / M, oxygen supply pressure 0.15M
The substrate was subjected to plasma treatment under the conditions of Pa and treatment time of 10 minutes.

Example 4 In the step (7) of C of Example 1, plasma treatment and oxidation treatment were performed in this order on the entire upper surface of the substrate including the surface of the groove formed in the substrate under the following conditions. After forming the coupling agent layer,
An optical fiber array was manufactured in the same manner as in Example 1. That is, while using a plasma screening device (Kyushu Matsushita Electric Co., Ltd., PC12F-G type) in a vacuum state,
Plasma irradiation amount 800 W, oxygen supply amount 300 sec. /
After subjecting the substrate to plasma treatment under conditions of M, oxygen supply pressure of 0.15 MPa and treatment time of 10 minutes, the substrate was immersed in a fuming nitric acid solution (concentration 3% by weight, liquid temperature 60 ° C.) for 10 minutes. The surface of the groove after the above-mentioned oxidation treatment was treated with E as in the second embodiment.
When measured by SCA, it was confirmed that an oxide film was present on the surface of the groove, and the degree of oxidation was 15 nm.

(Example 5) In the step B of Example 1 (preparation of the lid portion), borosilicate glass (Pyrex (R)) was used.
To store the exposed optical fibers having different depths and the optical fiber ribbon together with the coating resin layer by cutting the substrate made of A lid 170 having a concave portion 172 and a concave portion 172 of FIG.
In the step (8) of C, the optical fiber array 101 was manufactured in the same manner as in Example 1 except that the lid portion 170 was attached to the substrate (see FIG. 8B).

Regarding the optical fiber arrays obtained in Examples 1 to 5, a cycle of holding at 130 ° C. for 3 minutes and at −65 ° C. for 3 minutes was defined as 1 cycle, and this cycle was set to 10 cycles.
A reliability test was repeated for 100 cycles, after which the optical fiber array was cut in the axial direction of the optical fiber so as to pass through the optical fiber, and the cross section was observed.

As a result, in the optical fiber arrays of Examples 1 to 5, no peeling between the adhesive and the substrate was observed, and no crack was generated in the adhesive.
Further, when the optical fiber arrays of Examples 1 to 5 before the reliability test were disassembled and the filling state of the adhesive was observed, it was found that the gap between the groove and the optical fiber and the gap between the lid portion and the optical fiber were It was completely filled with the adhesive, and no void was found in the adhesive.

Further, when the optical fiber arrays of Examples 1 to 5 were connected to a light receiving device having eight light receiving elements and the coupling loss was measured, the coupling loss was low and the quality required as a product was obtained. I was fully satisfied.

[0172]

As described above, since the optical fiber array of the present invention has the above-mentioned structure, the surface of the groove and the adhesive have excellent adhesiveness. In the optical fiber array, the surface of the groove is excellent. It is possible to accurately transmit an optical signal without peeling between the adhesive and the adhesive or a positional deviation of the optical fiber. In addition, in the optical fiber array of the present invention, at the time of manufacturing, when the uncured adhesive is poured from the end surface of the groove, the uncured adhesive is uniformly poured into the gap between the groove and the optical fiber, Voids do not occur in the adhesive after the curing treatment.

[Brief description of drawings]

FIG. 1A is a partial perspective view schematically showing an example of an optical fiber array of the present invention, and FIG. 1B is a part A of FIG.
FIG.

FIG. 2A is a partial perspective view schematically showing an example of the optical fiber array of the present invention in which a lid is formed,
(B) is a perspective view showing only the lid part attached to the optical fiber array, and (c) is a sectional view taken along the line AA of (a).

3A is a partial perspective view schematically showing an example of an optical fiber array of the present invention using a laminated optical fiber ribbon, and FIG. 3B is a sectional view taken along line AA of FIG. Is.

4A to 4F are cross-sectional views showing an example of a method for forming a groove in a substrate.

FIG. 5 is a partial perspective view schematically showing an embodiment of a laminated optical fiber ribbon.

6A and 6B are perspective views schematically showing a part of the manufacturing process of the optical fiber array of the present invention.

7A and 7B are perspective views schematically showing a part of the manufacturing process of the optical fiber array of the present invention.

8A and 8B are perspective views schematically showing a part of the manufacturing process of the optical fiber array of the present invention.

[Explanation of symbols]

110 optical fiber ribbon 115, 235, 245 optical fiber 151,251 substrate 157,257 groove 160, 170 lid 100,200 Fiber Optic Array 210 laminated optical fiber ribbon

Claims (7)

[Claims] 1. A plurality of grooves are formed in a part of the upper surface of the substrate,
An optical fiber array in which an optical fiber is housed in the groove via an adhesive, wherein a coupling agent layer is formed on at least the surface of the groove. 2. The upper surface of the substrate including the surface of the groove, and / or
Alternatively, the optical fiber array according to claim 1, wherein a coupling agent layer is formed on a surface of the optical fiber. 3. The optical fiber array according to claim 1, wherein a lid is formed on the substrate. 4. A coupling agent layer is formed on at least one of the upper surface of the substrate including the surface of the groove, the surface of the lid portion facing the substrate, and the surface of the optical fiber. Item 3. The optical fiber array according to Item 3. 5. The optical fiber array according to claim 1, wherein the coupling agent layer is formed by using epoxysilane and / or imidosilane. 6. A method of manufacturing an optical fiber array comprising at least the following steps (A) to (D): (A) Groove forming step of forming a plurality of grooves on a part of the upper surface of the substrate, (B) Coupling agent layer forming step of forming a coupling agent layer on at least the surface of the groove, (C) Optical fiber in the groove Optical fiber storing step for storing
(D) An adhesive filling step of filling an uncured adhesive into the optical fiber non-enclosed portion of the groove. 7. The method of manufacturing an optical fiber array according to claim 6, wherein at least the surface of the groove is subjected to plasma treatment and / or oxidation treatment before the step (B).